The Arytenoid Cartilages (cartilagines arytænoideæ) are two in number, and situated at the upper border of the lamina of the cricoid cartilage, at the back of the larynx. Each is pyramidal in form, and has three surfaces, a base, and an apex.
The posterior surface is a triangular, smooth, concave, and gives attachment to the Arytænoidei obliquus and transversus.
The antero-lateral surface is somewhat convex and rough. On it, near the apex of the cartilage, is a rounded elevation (colliculus) from which a ridge (crista arcuata) curves at first backward and then downward and forward to the vocal process. The lower part of this crest intervenes between two depressions or foveæ, an upper, triangular, and a lower oblong in shape; the latter gives attachment to the Vocalis muscle.
The medial surface is narrow, smooth, and flattened, covered by mucous membrane, and forms the lateral boundary of the intercartilaginous part of the rima glottidis.
The base of each cartilage is broad, and on it is a concave smooth surface, for articulation with the cricoid cartilage. Its lateral angle is short, rounded, and prominent; it projects backward and lateralward, and is termed the muscular process; it gives insertion to the Cricoarytænoideus posterior behind, and to the Cricoarytænoideus lateralis in front. Its anterior angle, also prominent, but more pointed, projects horizontally forward; it gives attachment to the vocal ligament, and is called the vocal process.
The apex of each cartilage is pointed, curved backward and medialward, and surmounted by a small conical, cartilaginous nodule, the corniculate cartilage.